Shannon Liss-Riordan on Monday filed a class-action lawsuit in federal court in Manhattan on behalf of three former IBM employees who say the tech giant discriminated against them based on their age when it fired them. Liss-Riordan, a partner at Lichten & Liss-Riordan in Boston, has represented workers against Amazon, Uber and Google and has styled her firm as the premier champion for employees left behind by powerful tech companies.

“Over the last several years, IBM has been in the process of systematically laying off older employees in order to build a younger workforce,” the former employees claim in the suit, which draws heavily on a ProPublica report published in March that said the company has fired more than 20,000 employees older than 40 in the last six years.

​The lawsuit comes as IBM faces questions about its firing practices. In exhaustive detail, the ProPublica report made the case that IBM systematically broke age-discrimination rules. Meanwhile, the Equal Employment Opportunity Commission has consolidated complaints against IBM into a single, targeted investigation, according to a person familiar with it. A spokeswoman for the EEOC declined to comment.